Alarm clock



H, JUNGHANS ALARM CLOCK Filed May 4, 1936 2 Sheets-Sheet 1 five f /7e 2777a? Juwgllamy Aug. 22, 1939.

H JUNGHANS ALARM CLOCK Filed May 4, 1936 2 Sheets-Sheet 2 llll ,...1lil l Patented Aug. 22, 1939 PATENT OFFICE ALARM CLOCK Helmut Junghans, Eckenhof in Sulgen, near Schramberg, Germany Application May 3., 1936, Serial No. 77,893 In Germany April 8, 1935 4 Claims.

The invention relates to an alarm clock having a clock-movement adapted to run for one or for several days.

It is the object of the invention to provide in connection with clocks of this kind a stopping device which enables the alarm mechanism to be re-Wound immediately after the same has run down, but which at the same time is so constructed that the alarm mechanism will not continue to be checked indefinitely by reason of its actuation, and thus prevented from functioning upon the next occurrence of the adjusted time.

Other objects and advantages of the invention will become apparent as the description proceeds.

Alarm clocks as heretofore in use will only permit of a re-winding of the alarm mechanism immediately after it has run down, without varying the setting of the alarm hand, by actuation of the stopping device which checks the function of the alarm mechanism, in which case there is always the danger that one may fail to return the stopping device to the position of release, or it is necessary to defer the re-winding for a period of 1 to 1% hours. In each case there is the disadvantage that the alarm mechanism will be caused to function within the next 12 hours, whereas in the majority of cases it would be preferable to be able to set the alarm mechanism to function at a certain time within an additional period of 12 hours, or in the case of an eight-day clock after a correspondingly longer interval.

According to the invention, this drawback is eliminated by the provision of a stopping device which is caused to be engaged for the purpose of locking the alarm mechanism when the latter is re-wound, and which is coupled with the clockmovement to be released automatically as the clock advances. Preferably, this automatic disengagement is made to be dependent in such fashion on the advance of time as shown by the clock that the period of time elapsing between the locking and the release of the alarm mechanism is adjustable as desired; for example in the case of a tWenty-four-hour clock it may be set to function within the next 12 or 24 hours, or in the case of an eight-day clock within the same period or within a multiple thereof.

According to an additional feature of the invention, the return movement of the stopping device from the locked position to the position of release is derived from the rotary movement of the winding spindle of the clock-movement. The movement of the winding spindle is transmitted to the stopping lever by means of a cam.

In accordance with the invention, the return of the stopping lever to the position of release may be performed in two structurally difierent ways, via, either by co-operation of the stopping lever with a thread cut deeply into the spindle of the barrel of the clock-movement, which moves the correspondingly constructed stopping lever along its axis of rotation out of the locked position into the position of release, or by means of a helix in a flat disc mounted on the said spindle, which helix controls a stopping lever adapted to rock about a fixed point.

The actuating elements for the stopping device may be provided either on the back of the clock or in the usual fashion at the top of the clock casing, and they are so constructed that their actuation is equally as simple as that of existing devices and confusion is quite out of the question.

The invention will now be described more fully with reference to the accompanying drawings, in which Figs. 1-3 illustrate in elevational, end elevational and plan views respectively a possible form of embodiment of the invention, making use of a thread as aforesaid for controlling the alarm mechanism, the parts being shown in the locked position.

Figs. 4-6 show a second form of embodiment, in which the stopping lever is controlled by a helix, Fig. 4 being a front elevation showing the parts in the locked position, Fig. 5 a similar view showing the parts in the position of release, and Fig. 6 a plan view in which the parts are also looked. Fig. 7 is a side view on an enlarged scale to show the shape of the guide pin.

In the form of embodiment according to Figs. 1 to 3 there is employed for the return of the stopping lever an ordinary thread I provided in the spindle 2 of the main-spring 3. The stopping lever 4 engages with its arm 5 in the thread I and upon the advance or running of the clock is moved, with axial displacement of its extended pivot 6, out of the locked position into the position of release (Figs. 1 and 3). That is, upon the running of the clock by the rotating spindle and the arm 5 of the lever 4 contacting in the threads I of this spindle, the latter will finally be moved back in an axial direction of its pivot 6. The wire 1 on the shaft of the hammer is thus released from the action of the lever 4 and now co-operates in the known fashion with the spring 8, which causes the actuation of the alarm mechanism at the time adjusted by the spindle of the alarm hand.

The stopping device is actuated by turning the button 9 counterclockwise against the action of spring H and pushing it inwardly to advance the lever 4 until it moves below the wire 1 at any time prior to re-winding the alarm mechanism after the latter has run down.

This displacement is rendered possible by the fact that the lever 4 rotatable about its pivot 6 is pressed with its arm 5 into the thread I under the action of spring II which acts on the arm 10 and upon the displacement of lever 4 slides along the said arm. If it is desired to set the clock so that the automatic release will take place a little less than 12 hours after Winding the alarm, the

lever is set so that the arm rests in the groove of the thread I at about its mid-portion and if it is desired to set the clock so that the auto-.

matic release will take place only after a little less than 24 hours after the alarm is wound, the lever l is set so that the arm 5 rests in the groove of the thread I at a point adjacent one end of the thread as shown, at the end adjacent the alarm spring. By the use of conventional transmission members the button 9 may also be adapted to be operated from the top of the clock casing.

When the time spring is wound the spindle 2 will be turned in a counterclockwise direction, thus tending to cause the lever 4 to be moved toward the spring 3 but since it has already been moved to this position and before winding of the alarm, the arm 5 will be moved up out of the thread I and drop again in engagement therewith at the end of each revolution of spindle 2, since this is the end of the thread when spindle 2 is turned in a counterclockwise direction. However, when the spindle turns in a clockwise direction upon operation and unwinding of the time spring, the point adjacent the spring 3 is then considered as the beginning of the thread I and the arm 5 and lever 4 will be caused to recede from the spring 3 and thus release the lever 4 from the wire 7.

The second form of embodiment (Figs. 4 to 6) makes use of a spiral groove llll for the release of the stopping lever. This spiral groove is provided in the disc :92, commencing in the vicinity of the axis thereof and ending at the periphery of the disc, the said disc in turn being mounted firmly on the arbor I 63 of the main-spring I04. The said spiral groove co-operates with a guide pin H2 on the guide arm m5 of the stopping lever m1, which is capable of rocking under frictional braking action about a fixed point IE6, and it moves the said arm, as the clock-movement advances, out of engagement with the escapement wheel I68 locked thereby. Preferably the spiral groove 56! does not terminate as such into the periphery of the disc, but merges into a cut-out portion I89 having rather steep sides, which moves the lever llll more rapidly out of reach of the teeth of the escapement wheel I 08 in that the pin l l2 is rapidly moved onto the periphery of the disc particularly upon slow movement. In this way there is prevented an undesirable wear on the wheel H18 by impact with the stopping lever.

The guide arm 155 is obviously flexible or elastic in order that it can be set to any desired point in the spiral groove lill. V

The actuation of the stopping device takes place by means of an arm Hi3. This arm, with the assistance of a marking Ill, is adjusted at any desired time before rewinding after the alarm mechanism has run down for release of the alarm mechanism at any hour during the following l2 or 24 hours or the desired multiple thereof. By reason of this adjustment it is accomplished on the one hand that the lever IE7 is moved into locking engagement with the escapement wheel H38 and on the other hand that the control arm I05 is introduced with its guide pin H2 into the turn of the spiral groove NH which corresponds with the adjusted period of time. This adjustment is rendered possible by the fact that the arm. Hi5, which is preferably stamped together with the stopping lever in one piece composed of sheet metal is situated with its wide portion opposite the disc E02 and is capable of flexing perpendicularly with respect thereto, so that the guide pin moves without difliculty over the crest of the spiral groove.

As the clock advances the alarm mechanism is released from the control of the locking lever l0! after elapse of the period adjusted by lever H0 and now co-operates with the spring H3, upon the release of which allows the alarm mechanism to be actuated at the time indicated by, and to which the spindle of the alarm hand has been adjusted.

The stopping device according to the invention considerably improves the utility of the clock. The automatic release precludes the possibility of an unintentional locking of the alarm mechanism. The parts are simple, reliable and cheap in the manufacture and assembly, so that their provision in the clock does not represent any appreciable increase in the cost of production.

What I claim as new and desire to secure by Letters Patent is:

1. In an alarm clock, analarm mechanism, a thread on the arbor of the main spring of the clock movement, a stopping lever adapted to lock the said alarm mechanism, an arm on the said lever engaging in the said thread and adapted to be shifted axially of the arbor by the said thread as the clock movement advances for the purpose of releasing the said alarm mechanism, and means indicating the point of introduction of the said arm in the said thread for the purpose of adjusting as desired the time of release of the said alarm mechanism.

2. In an alarm clock, an alarm(mechanism, a disc mounted firmly on the arbor of the mainspring of the clock movement, said disc having a spiral groove commencing near the centre thereof and extending to the periphery of the said disc, a stopping lever adapted to lock the said alarm mechanism, an arm on the said lever engaging in the said groove and adapted to leave the groove as the clock movement advances for the purpose of releasing the said alarm. mechanism.

3. In an alarm clock, an alarm mechanism, a disc mounted firmly on the arbor of the mainspring of the clock movement, said disc having a spiral groove commencing near the centre thereof and terminating at the periphery in. a cut-out portion, a stopping lever adapted to lock the said alarm mechanism, and an arm on the said lever engaging in the said groove and adapted to leave the groove as the clock movement advances for the purpose of releasing the said alarm mechanism.

4. In an alarm clock, an alarm mechanism, a disc mounted firmly on the arbor of the mainspring of the clock movement, said disc having a spiral groove commencing near the centre thereof and extending to the periphery of the said disc, a stopping lever adapted to lock the said alarm mechanism, a flexible arm on the said lever engaging in the said groove and adapted to leave the groove as theclock movement advances for the purpose of releasing the said alarm mechanism, and means indicating the point of introduction of the said arm into the said groove for the purpose of adjusting as desired the time of release of the said alarm mechanism.

HELMUT J UNGHANS. 

